Vacuum circuit breaker



FIG. 1 is a front, top and left side perspective view of a vacuum circuit breaker, showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken line portion of the figures is included to show unclaimed subject matter only and forms no part of the claimed design. 

CLAIM The ornamental design for a vacuum circuit breaker, as shown and described. 